Based on the settlement price. The settlement price refers to the weighted average price of the transaction price of the futures contract on the same day according to the volume. If there is no transaction on that day, the settlement price of the previous trading day shall be the settlement price of that day. The settlement price of a futures contract on the previous trading day plus the maximum allowable increase constitutes the upper limit of the price increase on that day, which is called the daily limit, and the settlement price of the previous trading day minus the maximum allowable decrease constitutes the lower limit of the price decrease on that day, which is called the daily limit.